A portable hard drive is one of the most convenient ways to take large files around with you. The problem with a portable hard drive is the fact that it is so mobile. If you lose your hard drive or leave it out in the open, the contents could be in jeopardy. The best way to secure your hard drive is to password-protect the files inside. To do this you will need to consolidate all of the files to one folder.
Plug your USB hard drive into an available USB port on your computer.
Click on the "Start" button on the lower left-hand side of the screen and select "My Computer" from the choices given.
Click on your USB hard drive's icon in the "My Computer" screen.
Right-click on the white area of the contents portion and select "New Folder" from the choices given.
Label your new folder with an appropriate name. Consolidate all of the files from the USB hard drive into your new folder by dragging them all into the folder.
Right-click on the folder and select "Properties".
Click on the "Sharing" tab and then click on the small box that reads "Make This Folder Private".
Click on the "Apply" tab, and then click on the "OK" tab.
Return to your folder and try to open it. Enter the password you use to log into your system and you will have access to the file along with all of the contents.